1Z0-184-25 Question 24
Select 2You are managing an Oracle Database on Oracle Cloud Infrastructure (OCI) that stores vector embeddings for real-time similarity searches. After retraining your machine learning model, you need to update the vector values for a subset of rows. Which two approaches ensure that the vector index remains accurate for subsequent similarity queries? (Choose two.)
- A
Use a standard UPDATE statement on the vector column and perform a manual index synchronization if the index is not set to auto-maintenance.
- B
Directly modify the vector index metadata to reflect the new vectors without issuing a database UPDATE command.
- C
Execute a MERGE statement that includes changes to the vector column, relying on Oracle Database to maintain the vector index if automatic synchronization is enabled.
- D
Drop the table and its vector columns altogether, re-create it with the updated embeddings, and then re-establish the index.
Show answer and explanation
Correct answers: A, C
Explanation
When performing DML operations on tables containing vector data, Oracle Database allows you to use standard SQL constructs (e.g., UPDATE, MERGE) to modify vector columns. If the vector index does not automatically maintain itself, you must perform an index synchronization or rebuild step to keep the index current. Refer to official Oracle documentation for details on index rebuilds, syncing methods, and auto-maintenance settings to avoid inconsistent or outdated vector searches.
- A. Correct.
Correct. A standard UPDATE on the vector column is the typical approach for row-level changes. If your vector index does not support automatic maintenance, you must manually sync or rebuild the index afterward via an ALTER INDEX or similar maintenance operation to ensure the index accurately reflects the new vectors.
- B. Incorrect.
Incorrect. Manually editing index metadata without performing actual DML operations on the table is not a supported way to update data in Oracle. Indexes must track the underlying table data, not the other way around.
- C. Correct.
Correct. A MERGE statement that modifies the vector column can work particularly well in batch or conditional updates. If your environment supports and has enabled automatic index maintenance, Oracle Database will handle the index synchronization in the background, ensuring the vector index remains up to date.
- D. Incorrect.
Incorrect. Dropping and re-creating the entire table is overly disruptive and unnecessary. While rebuilding an index may sometimes be recommended in large-scale or bulk updates, completely removing and re-creating the table introduces avoidable downtime and complexity.